The 3-month-old royal baby was christened today, ritually welcomed into the Church of England as Prince George Alexander Louis of Cambridge, in a private ceremony for close family and friends in the historic chapel of a London royal palace.

His parents, Prince William and Duchess Kate of Cambridge, grandparents, great-grandparents and seven godparents looked on as the baby was baptized by the Archbishop of Canterbury Justin Welby, in an antique silver font in the Chapel Royal of St. James's Palace as a small scarlet-and-gold-clad choir sang hymns.

The christening, blending tradition and innovation, was yet another display of the young royals' savvy approach to duty, history, modernity and informality, obvious since their engagement in 2010.

The baby appeared to be happy and not crying before the ceremony began, as his royal relatives and godparents arrived at the chapel.

The guest list for the ceremony was short, just 22 people and only five royals: great-grandparents Queen Elizabeth II and Prince Philip, grandfather Prince Charles and his wife, Camilla Duchess of Cornwall, and Prince Harry. Also there were maternal grandparents Michael and Carole Middleton, Kate's siblings Pippa and James Middleton, plus the closest relatives and oldest friends of the Duke and Duchess of Cambridge.

The godparents, as disclosed by the palace six hours before the ceremony, include the single royal, William's cousin, Zara Phillips Tindall, the queen's granddaughter and daughter to Princess Anne the Princess Royal (who is in Canada). An Olympic equestrian champion, she's married to ex-rugby player Mike Tindall and is pregnant with her first child.

The other godparents are Oliver Baker, an old college friend of the couple; Emilia Jardine-Patterson (formerly d'Erlanger), a high school friend of Kate's and old friend to Will, who introduced them; Hugh, Earl Grosvenor, son of the Duke of Westminster and old friend of Will and Harry; Jamie Lowther-Pinkerton, the couple's former private secretary who still advises them and whose son was in the royal wedding; Julia Samuel, a close friend of Will's late mother, Princess Diana; and William van Cutsem, one of Will's closest childhood friends and son of Prince Charles' close friend Hugh van Cutsem, who died a few weeks ago. The van Cutsem family provided a refuge for William and Harry during their parents' bitter divorce; Will is godfather to van Cutsem's daughter Grace who was in the royal wedding.

The list of guests was notable for the absence of such senior royals as the queen's three other children, Prince Andrew, Princess Anne and Prince Edward, all of whom were busy with royal duties elsewhere. The royal couple sought a low-key ceremony in contrast to their wedding extravaganza in 2011.

Several of the godparents' names were a surprise; others had already been discussed earlier in British media reports about how Will and Kate broke with tradition in choosing old friends as godparents for their first child, third-in-line to the throne, rather than foreign royals, as with William himself. Prince Charles, for instance, had nine official godparents, including two kings, one queen, one princess and one prince.

After the ceremony, the palace said, Prince Charles hosted a tea party at his London residence, Clarence House, where the guests were served the traditional slices of christening cake, a tier taken from Will and Kate's wedding cake, an eight-tier fruit-infused confection designed by celebrated pastry maker Fiona Cairns.

Photographers were stationed outside the palaces to cover the arrivals and departures but did not have access to the chapel ceremony.

Duchess Kate and Prince William arrived by car, he in the front seat, she in the back with the baby in a car seat. She was wearing a cream-colored bespoke dress by Alexander McQueen and a matching fascinator-type hat by Jane Taylor, according to a tweet by the Daily Mail's royal reporter, Rebecca English.

The historic picture of the queen and three generations of her heirs (the first such picture since Queen Victoria in 1894) will be released by the palace Thursday morning. (The palace said Tuesday the photographer will be Jason Bell, 44, best known for his Hollywood celebrity portraits in Vogue and Vanity Fair.)

It was raining heavily in London today but that didn't stop royal fans, some outfitted in colorful gear, from gathering outside the chapel early, some as early as days before. Beneath a blue tarp, seven die-hard royalists slept overnight on the sidewalk in anticipation.

"My future king knows I've been here all night," Julie Cain, 50, of New Castle, said. "It gives you a sense of pride."

Sitting in lawn chairs set up across from where the queen will enter the christening, and adorned with Union Jack paraphernalia, these well-wishers have followed royal family events for decades.

"This is a historic moment," said John Loughrey, 58, of London, a self-proclaimed "Diana super fan." "Princess Diana will be giving her special love today."

Decked out in a Union Jack suit, Terry Hutt, 78, spent hours this morning stringing British flags to the barricades across the street from St. James's Palace. Hutt, who spent 12 days outside the Lindo Wing awaiting Prince George's birth in July, has followed every royal event since he met the late Queen Mother Elizabeth at age 4.

"I'd like to think that I've become a royal family godparent of sorts," Hutt said.

Susanne Hallwarth, 53, of Northern Ireland, planned a visit to see her son so it would overlap with the christening. She has attended each of the royal events since her son began working in Buckingham Palace around the time of the royal wedding in 2011.

"They're wonderful; I'm such a big fan," said Hallworth, who's a civil servant. "It's a once-in-a-lifetime chance to be with four generations of heirs at once."

The ceremony was short, less than 45 minutes, and took place in private, as is typical for royal christenings. Not typical was the venue: Most royal babies, including William, Charles and the queen, were christened in the Music Room of Buckingham Palace. The last royal baby to be christened in the Chapel Royal was Princess Beatrice, William's cousin, in 1988.

For the service, the Cambridges chose two hymns, two lessons and two anthems, the palace said. The hymns are Breathe on Me, Breath of God and Be Thou My Vision. The lessons are from St. Luke ch. 18, verses 15-17, read by Pippa Middleton, and St. John ch. 15, verses 1-5, read by Prince Harry. The anthems are Blessed Jesu! Here we Stand (Richard Popplewell) and The Lord Bless You and Keep You (John Rutter).

Compared to most rooms in Buckingham Palace, the Chapel Royal, started by Henry VIII in 1540, is much more intimate, with purple velvet-cushioned bench seating for about 40 people, beautiful stained-glass windows and gilded ceilings.

Like so many royal buildings in the U.K, the chapel has a rich history. It is believed to be the burial place of the heart of Queen Mary I, the elder daughter of Henry VIII. It's where her younger sister Queen Elizabeth I waited and prayed during the Spanish Armada crisis in 1588. It was where Charles I received last rites before his head was chopped off in Whitehall in 1649. And it was where Queen Victoria married her Prince Albert in 1840.

But its real historic significance to the royal couple is its poignant association with the princess who would never be queen: Diana, William's late mother. After she was killed in a Paris car crash in 1997, her coffin lay before the chapel's altar until her funeral in Westminster Abbey.

Baptism is an important religious ritual in the Christian faith but it's especially important to British royals: Since the monarch is the head of the Church of England, eventually Prince George will take on that role so it's critical that he be raised as an Anglican.

Kensington Palace posted pictures of past royal christenings on the Cambridge website and then tweeted out the link about five hours before the ceremony.

The 17-inch-high silver-gilt baptismal font, the Lily Font, is part of the Crown Jewels collection kept at the Tower of London; it was moved to the chapel for the ceremony and contained water from the River Jordan, the palace said. Made for the baptism of Queen Victoria's first child, the carved baptismal font has been used for the christening of every royal baby since the little Princess Victoria in 1841.

Prince George wore a handmade replica of the christening gown first made for and worn by little Princess Victoria in 1841 and every royal baby up to 2008. Made of silk and fine Honiton lace lined with white satin, it was, by 2008, too fragile for further use, so the queen commissioned a replica from her dressmaker Angela Kelly.

The last royal baby to be christened in the new robe, in March 2013, was Isla Elizabeth Phillips, the second child of the queen's eldest grandson, Peter Phillips, and her second great-grandchild.

Archbishop Welby said in public remarks several days before the ceremony that he planned to baptize the baby with a few drops of water, rather than the immersion custom of some Protestant faiths. Welby also said he hoped Prince George's christening and the attention it attracted would be good for the Anglican church and inspire other parents to do the same with their newborns.